Archetypes of incomplete stories in chronic illness medical encounters.

OBJECTIVE: During encounters, patients and practitioners engage in conversations to address health concerns. Because these interactions are time-pressured events, it may be inevitable that any story exchanged during these encounters will be incomplete in some way, potentially jeopardizing how quality and safety of care is delivered. In this study, we explored how and why incomplete stories might arise in health interactions. METHODS: Constructivist grounded theory methodology was used to explore how patients and practitioners approach their interactions during encounters. In this two-phase study, we interviewed patients (n = 21) then practitioners (n = 12). RESULTS: We identified three distinct archetypes of incomplete storytelling - the hidden story, the interpreted story, and the tailored story. Measured information sharing, triadic encounters and pre-planned agendas influenced these storylines, respectively. CONCLUSION: Both patient and practitioner participants focused on what each considered important, appropriate, and useful for productive encounters. While incomplete stories may be a reality, educating practitioners about how incomplete stories come about from both sides of the conversation creates new opportunities to optimize interactions at medical encounters for in-depth patient practitioner storytelling.

The non-dystrophic myotonias: molecular pathogenesis, diagnosis and treatment.

The non-dystrophic myotonias are an important group of skeletal muscle channelopathies electrophysiologically characterized by altered membrane excitability. Many distinct clinical phenotypes are now recognized and range in severity from severe neonatal myotonia with respiratory compromise through to milder late-onset myotonic muscle stiffness. Specific genetic mutations in the major skeletal muscle voltage gated chloride channel gene and in the voltage gated sodium channel gene are causative in most patients. Recent work has allowed more precise correlations between the genotype and the electrophysiological and clinical phenotype. The majority of patients with myotonia have either a primary or secondary loss of membrane chloride conductance predicted to result in reduction of the resting membrane potential. Causative mutations in the sodium channel gene result in an abnormal gain of sodium channel function that may show marked temperature dependence. Despite significant advances in the clinical, genetic and molecular pathophysiological understanding of these disorders, which we review here, there are important unresolved issues we address: (i) recent work suggests that specialized clinical neurophysiology can identify channel specific patterns and aid genetic diagnosis in many cases however, it is not yet clear if such techniques can be refined to predict the causative gene in all cases or even predict the precise genotype; (ii) although clinical experience indicates these patients can have significant progressive morbidity, the detailed natural history and determinants of morbidity have not been specifically studied in a prospective fashion; (iii) some patients develop myopathy, but its frequency, severity and possible response to treatment remains undetermined, furthermore, the pathophysiogical link between ion channel dysfunction and muscle degeneration is unknown; (iv) there is currently insufficient clinical trial evidence to recommend a standard treatment. Limited data suggest that sodium channel blocking agents have some efficacy. However, establishing the effectiveness of a therapy requires completion of multi-centre randomized controlled trials employing accurate outcome measures including reliable quantitation of myotonia. More specific pharmacological approaches are required and could include those which might preferentially reduce persistent muscle sodium currents or enhance the conductance of mutant chloride channels. Alternative strategies may be directed at preventing premature mutant channel degradation or correcting the mis-targeting of the mutant channels.

The primary periodic paralyses: diagnosis, pathogenesis and treatment.

Periodic paralyses (PPs) are rare inherited channelopathies that manifest as abnormal, often potassium (K)-sensitive, muscle membrane excitability leading to episodic flaccid paralysis. Hypokalaemic (HypoPP) and hyperkalaemic PP and Andersen-Tawil syndrome are genetically heterogeneous. Over the past decade mutations in genes encoding three ion channels, CACN1AS, SCN4A and KCNJ2, have been identified and account for at least 70% of the identified cases of PP and several allelic disorders. No prospective clinical studies have followed sufficiently large cohorts with characterized molecular lesions to draw precise conclusions. We summarize current knowledge of the clinical diagnosis, molecular genetics, genotype-phenotype correlations, pathophysiology and treatment in the PPs. We focus on unresolved issues including (i) Are there additional ion channel defects in cases without defined mutations? (ii) What is the mechanism for depolarization-induced weakness in Hypo PP? and finally (iii) Will detailed electrophysiological studies be able to correctly identify specific channel mutations? Understanding the pathophysiology of the potassium-sensitive PPs ought to reduce genetic complexity, allow subjects to be stratified during future clinical trials and increase the likelihood of observing true clinical effects. Ideally, therapy for the PPs will prevent attacks, avoid permanent weakness and improve quality of life. Moreover, understanding the skeletal muscle channelopathies will hopefully lead to insights into the more common central nervous system channel diseases such as migraine and epilepsy.

Effect of ketoconazole on ritonavir and saquinavir concentrations in plasma and cerebrospinal fluid from patients infected with human immunodeficiency virus.

AIM: Our aim was to evaluate the effect of ketoconazole on ritonavir and saquinavir plasma and cerebrospinal fluid (CSF) concentrations. METHODS: Twelve patients who were human immunodeficiency virus-seropositive and who were receiving 400 mg of ritonavir and 400 mg of saquinavir twice daily completed a nonfasted, two-period, two-group, longitudinal pharmacokinetic study. Blood samples were collected over the daytime 12-hour dosing interval of the protease inhibitors at baseline (period 1, day 0) and after 10 days of coadministration of 200 mg (n = 6) or 400 mg (n = 6) of ketoconazole once daily (period 2, day 10). One set of paired CSF and blood samples was collected between 4 and 5 hours after the dose on both days. RESULTS: Ketoconazole significantly increased area under the plasma concentration-time curve, plasma concentration at 12 hours after the dose, and half-life of ritonavir by 29% (95% confidence interval (CI), 13%-46%), 62% (95% CI, 37%-92%), and 31% (95% CI, 13%-51%), respectively. Similar increases of 37% (95% CI, 4%-81%), 94% (95% CI, 41%-167%), and 38% (95% CI, 15%-66%), respectively, were observed for these parameters for saquinavir. Ketoconazole significantly elevated ritonavir CSF concentration by 178% (95% CI, 59%-385%), from 2.4 to 6.6 ng/mL, with no change in paired unbound plasma level (26 ng/mL); this led to a commensurate 181% increase (95% CI, 47%-437%) in CSF/plasma unbound ratio. All pharmacokinetic changes were unrelated to ketoconazole dose or plasma exposures. Corresponding changes for saquinavir CSF pharmacokinetics were insignificant (P > .06); saquinavir CSF levels were unmeasurable in 7 patients (<0.2 ng/mL). CONCLUSIONS: The disproportionate increase in CSF compared with plasma concentrations of ritonavir is consistent with ketoconazole inhibiting both drug efflux from CSF and systemic clearance.

Differential expression and activity of p34cdc2 in cultured aortic adventitial fibroblasts derived from spontaneously hypertensive and Wistar-Kyoto rats.

OBJECTIVE: The present investigation was undertaken to determine whether p34cdc2, a cell-cycle regulatory kinase, is involved in the manifestation of the altered proliferation evident in fibroblasts isolated from spontaneously hypertensive rats (SHR). DESIGN: Experiments were performed on quiescent aortic adventitial fibroblasts stimulated to re-enter the cell cycle in order to examine the timing of cell cycle-related events. METHODS: The cell-cycle phase was determined by flow cytometry and was related to the cellular content and kinase activity of p34cdc2. RESULTS: SHR fibroblasts displayed a heightened basal level of p34cdc2 at quiescence relative to Wistar-Kyoto (WKY) rat cells. Both SHR and WKY fibroblasts showed a cell cycle-dependent increase in p34cdc2 content, beginning in S phase. However, the SHR adventitial fibroblasts exited G0-G1 several hours earlier than the WKY fibroblasts as indicated by the time of initiation of DNA synthesis and increase in activity of p34cdc2. CONCLUSIONS: SHR aortic adventitial fibroblasts appear to have a heightened proliferative capacity relative to WKY fibroblasts, which is evident in a quicker exit from G0 and faster transition to DNA synthesis, followed by the earlier activation of p34cdc2.

Contraction bands in visceral and vascular smooth muscle.

Smooth muscle contraction bands (SMCBs) have been described in the gastrointestinal tract, subsequent to acute ischemia, and in the coronary arteries of animals and individuals with a sudden death; in these circumstances SMCBs have been postulated to serve as a premortem marker, and suggested as diagnostically useful. The present investigation was undertaken to determine whether the presence of SMCBs could be correlated with a premortem clinical condition. Retrospectively, the routinely prepared histological sections from 76 autopsy and 93 surgical cases were screened semiquantitatively for the presence of SMCBs. The autopsy sections examined included the gastrointestinal tract, the prostate, and the coronary arteries, as well as all other smooth muscle-containing tissues; the surgical specimens included: coronary artery endarterectomies; saphenous vein bypass grafts; temporal artery biopsies; prostatic curettings; colectomies; varicose veins; leiomyomas of uterus, bowel, and skin; and, leiomyosarcomas. The clinical and pathology reports were reviewed for patient demographics, major clinical diagnoses, presence of shock, details of any resuscitation attempts, time interval to postmortem, and the cause of death. SMCBs were evident in 100% of the gastrointestinal and prostate, and in 96% of the coronary artery autopsy sections examined. All surgical specimens were positive for SMCBs, the exceptions being leiomyomas (positive in 13 of 22; 60%) and leiomyosarcomas (4 of 5; 80%); SMCBs in surgical specimens were less prominent when compared with those observed in autopsy tissue. No correlation was found between the presence of SMCBs and any clinical or demographic parameter assessed, because of the virtual universal occurrence of the SMCBs. The presence of less distinct SMCBs in surgical specimens may very well be artifactual, akin to myocardial and skeletal muscle contraction bands. The observation that SMCBs at autopsy are virtually ubiquitous suggests that they are best considered an agonal phenomenon, and a nonspecific pathological finding.

Ultrastructure of atrial and ventricular myocytes of newborn rats: evidence for the existence of specific atrial granule-like organelles in the ventricle.

The present study examined the ultrastructure of atrial and ventricular myocytes from the heart of newborn rats. It was found that, despite former reports stating that ventricular myocytes in adults do not contain cytoplasmic granules, specific atrial granule-like organelles are present in the ventricles of rats at birth. The presence of these granules together with the relatively underdeveloped contractile apparatus and extensive Golgi complex suggests that the ventricular, like the atrial, myocytes may have an endocrine function before or at birth. Further study is required to determine whether these ventricular cytoplasmic granules contain the same atrial natriuretic peptide species known to be present in the atrial specific granules.

CD30 positive (Ki-1) large cell lymphoma presenting with pericardial constriction.

It is very uncommon for the initial presentation of malignant lymphoma to be one of cardiac involvement and for such involvement to precipitate cardiac dysfunction attributable to constriction. We describe a CD30 positive (Ki-1) anaplastic large cell lymphoma, T-cell type, in a 29-year-old man whose presentation was a short history of profound hemodynamic impairment and whose clinical course was rapidly fatal. This patient's constrictive physiology was attributable to diffuse infiltration of the pericardium and epicardium by the Ki-1 lymphoma. Our description of this patient is noteworthy, given that the clinical and pathologic features of Ki-1 lymphomas are still being characterized.

The clinical and pathologic manifestations of iatrogenically produced mesothelium-rich fragments of operative debris.

OBJECTIVE: This report describes the clinical manifestations that may be associated with the amalgams of mesothelium and other debris which can be created iatrogenically when body cavities are opened or otherwise physically disturbed. METHODS: One autopsy and four surgical pathology cases are reviewed. Three of the studied patients had had recent cardiac surgery, one a laparotomy, and the fifth a thoracotomy. RESULTS: The series of five patients in this report demonstrates a wide range of manifestations when these tissue and debris amalgams are created. If the fragments gain an ingress to the vasculature, they may embolize and cause infarcts; if the origin of the amalgams is unappreciated, they may be confused with neoplasms; in other circumstances, the amalgams may represent incidental accompaniments of surgical specimens. CONCLUSION: Pathologists and clinicians should be aware of this recently described entity; only in the last couple of years has its pathogenesis been recognized. This report reviews an, until now, undescribed broad spectrum of clinical manifestations of these amalgams of iatrogenically created mesothelial and other operative debris.

Clinical features of facioscapulohumeral muscular dystrophy 2.

OBJECTIVE: In some 5% of patients with facioscapulohumeral muscular dystrophy (FSHD), no D4Z4 repeat contraction on chromosome 4q35 is observed. Such patients, termed patients with FSHD2, show loss of DNA methylation and heterochromatin markers at the D4Z4 repeat that are similar to patients with D4Z4 contractions (FSHD1). This commonality suggests that a change in D4Z4 chromatin structure unifies FSHD1 and FSHD2. The aim of our study was to critically evaluate the clinical features in patients with FSHD2 in order to establish whether these patients are phenotypically identical to FSHD1 and to establish the effects of the (epi-) genotype on the phenotype. METHODS: This cross-sectional study studied 33 patients with FSHD2 from 27 families, the largest cohort described to date. All patients were clinically assessed using a standardized clinical evaluation form. Genotype analysis was performed by pulsed field gel electrophoresis and PCR; D4Z4 methylation was studied by methylation-sensitive Southern blot analysis. RESULTS: FSHD2 is identical to FSHD1 in its clinical presentation. Notable differences include a higher incidence (67%) of sporadic cases and the absence of gender differences in disease severity in FSHD2. Overall, average disease severity in FSHD2 was similar to that reported in FSHD1 and was not influenced by D4Z4 repeat size. In FSHD2, a small effect of the degree of hypomethylation on disease severity was observed. CONCLUSIONS: Clinically, patients with FSHD2 are indistinguishable from patients with FSHD1. The present data suggest that FSHD1 and FSHD2 are the result of the same pathophysiologic process.

Expression profile of FSHD supports a link between retinal vasculopathy and muscular dystrophy.

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is caused by deletions within a tandem array of D4Z4 repeats on chromosome 4q35. In addition to muscle degeneration, most patients with FSHD develop abnormalities of the retinal vasculature. Previous work has suggested that muscle degeneration in FSHD results from increased expression of genes proximal to the deletion, including FRG1. OBJECTIVES: To reexamine this mechanism and identify pathways that are abnormally regulated early in the disease process. METHODS: We prospectively studied gene expression in skeletal muscle in patients with FSHD (n = 19) vs healthy individuals (n = 30) and patients with myotonic dystrophy type 1 (n = 12). We used oligonucleotide microarrays for global analysis of gene expression and reverse transcriptase-PCR (RT-PCR) to assess expression or alternative splicing for particular genes. RESULTS: Expression of FRG1 was not increased in patients with FSHD, either by microarray analysis or quantitative RT-PCR. Among genes on 4q35, only LRP2BP showed upregulation that was specific to FSHD. However, neither LRP2BP nor FRG1 showed imbalance of allelic expression by RT-PCR. After filtering out genes that showed similar dysregulation in other forms of muscular dystrophy, only 44 genes were specifically upregulated early in FSHD. Among these, 34 genes were characterized or partially characterized, of which 11 (32%) had a role in vascular smooth muscle or endothelial cells. CONCLUSION: Expression of genes on chromosome 4q35 was normally regulated in the early stages of facioscapulohumeral muscular dystrophy. Our results support a possible link between muscular dystrophy and retinal vasculopathy in facioscapulohumeral muscular dystrophy.

Cultured smooth muscle approach in the study of hypertension.

The systemic vasculature is known to undergo marked change in both human and experimental hypertension. The in vitro study of individual cellular components from the blood vessel wall and the regulation of their intracellular biochemical processes will aid in developing an understanding of the pathogenesis of hypertension. Vascular smooth muscle cells derived from the aorta and mesenteric arteries of normotensive and hypertensive rats can be successfully maintained in culture, providing a system free of confounding variables such as blood pressure. To assist in fully understanding the pathophysiology of hypertension, this cell culture model can be used to examine interactions between receptor and ligand, the transduction of an associated signal, characterization of subsequent intracellular responses and ultimately, quantification of a physiological and functional consequence of these events, for example, proliferation. The application of in vitro techniques to hypertension research will continue to contribute new knowledge to increase our understanding of the mechanisms behind the hypertensive disease process.

Isoproterenol exerts cyclic AMP independent effects on DNA synthesis in cultured adventitial fibroblasts from spontaneously hypertensive and Wistar-Kyoto rats.

Understanding the mechanism behind the growth response evident in the vasculature of the spontaneously hypertensive rat (SHR) remains elusive. Fibroblasts from the aortic adventitial layer of the SHR manifest the heightened proliferative rate in vitro relative to Wistar-Kyoto (WKY) rats that is conspicuous in cultured aortic smooth muscle cells. The adenylylcyclase/cyclic AMP signal transduction pathway is believed to be altered in hypertensive people and animals such that responses to beta-adrenoceptor activation are blunted. The present study examined the effects of beta-adrenoceptor-mediated versus direct activation of adenylylcyclase on intracellular cyclic AMP accumulation and subsequent DNA synthesis in cultured aortic fibroblasts. We hypothesized that elevation of cyclic AMP levels by both isoproterenol and forskolin would normalize the proliferative capacity of SHR fibroblasts. Forskolin increased intracellular cyclic AMP levels and inhibited epidermal growth factor stimulated thymidine incorporation in an equivalent manner in both SHR and WKY adventitial fibroblasts, implying that there is no difference in adenylylcyclase activity. Isoproterenol elevated cyclic AMP levels to a significantly greater degree in the SHR than did forskolin, and yet, relative to forskolin, attenuated growth factor induced DNA synthesis to a lesser extent. These data suggest that isoproterenol, via beta-adrenoceptor activation, exhibits both cyclic AMP dependent and cyclic AMP independent effects in adventitial fibroblasts. The cyclic AMP independent effects of isoproterenol oppose the expected observations due to cyclic AMP and may offer an explanation to the blunted responses to beta-adrenoceptor activation evident both in vitro and in vivo.

Forskolin and isoproterenol effect discrete responses on epidermal growth factor induced DNA synthesis in aortic smooth muscle cells.

Defining the mechanisms regulating the proliferation of vascular smooth muscle is necessary to better understand the pathogenesis of atherosclerosis and hypertension. In the present investigation, we examined the effects of incubation with forskolin or isoproterenol on the proliferation of cultured rat aortic smooth muscle cells. Forskolin, a direct activator of adenylate cyclase, and isoproterenol, a beta-adrenergic agonist, increased intracellular cyclic AMP levels in a concentration-dependent manner, subsequent to a 5-min exposure. Isobutylmethylxanthine at 100 microM attenuated epidermal growth factor stimulated DNA synthesis by 35% without affecting intracellular cyclic AMP levels. Forskolin dose-dependently augmented this inhibition. In contrast, a 24-h exposure of cells to isoproterenol resulted in a biphasic effect on growth factor stimulated thymidine incorporation. Both forskolin and isoproterenol attenuated thymidine incorporation to the same degree up to 12 h poststimulation, the onset of S phase. By 16 h poststimulation, [3H]thymidine incorporation in smooth muscle cells treated with isoproterenol was significantly enhanced by 50%, whereas forskolin treatment continued to attenuate DNA synthesis by 40%. Somewhat surprisingly, this disparity in effect on DNA synthesis was evident in spite of heterologous desensitization to rechallenge by either forskolin or isoproterenol subsequent to a 24-h incubation with either drug. These results suggest that the isoproterenol enhancement of epidermal growth factor stimulated DNA synthesis in rat aortic smooth muscle cells may be cyclic AMP independent.

Smooth muscle cell proliferation. Expression and kinase activities of p34cdc2 and mitogen-activated protein kinase homologues.

Rat vascular smooth muscle cells were synchronized to the quiescent state (G0) by serum deprivation and then stimulated to enter the cell cycle by serum refeeding. At various times of the cell cycle, cells were analyzed for the expression of p34cdc2 and mitogen-activated protein kinase homologues by immunoblotting and for kinase activity toward histone H1, myelin basic protein, and caldesmon. A small amount of p34cdc2 was expressed in the G0/G1 phase (0 to 8 hours). At the G1/S transition (12 hours), the level of p34cdc2 started to accumulate and increased by 60-fold at G2/M (18 hours), accompanied by a more slowly migrating band. Histone H1 kinase activity was undetectable in anti-p34cdc2 immunoprecipitates in the G0/G1 cells but appeared around the G1/S boundary and peaked at G2/M (18 hours). The caldesmon kinase activity exhibited two distinct phases: the first appeared at G0/G1 (0 to 8 hours), and the second appeared at G1/S and continued through G2/M. Two mitogen-activated protein kinase isoforms were expressed throughout the cell cycle. Anti-mitogen-activated protein kinase immunoprecipitates possessed kinase activities toward myelin basic protein and caldesmon, which were activated within 15 minutes after serum stimulation and declined within a few hours. These findings suggest that p34cdc2 and mitogen-activated protein kinase homologues may play significant roles in regulating the progression of the cell cycle of smooth muscle cells, the former at the G2/M transition and the latter at the G0/G1 transition.

Giant desmosomes in tumors.

The lengths of desmosomal profiles were measured in sections of tumor tissue from cases of mesothelioma, adenocarcinoma, squamous cell carcinoma, thymoma, and meningioma. Giant desmosomes (length of profile 1 micron or greater than 1 micron) were found in all the above-mentioned tumors except adenocarcinomas. The largest desmosomal profile in adenocarcinoma was approximately 0.8 micron long; the largest in mesothelioma was approximately 2 microns long. Our observations suggest that one of the ways in which giant desmosomes arise is by growth and fusion of adjacent desmosomes. Giant desmosomes may at times help in distinguishing mesothelioma from adenocarcinoma, but this is a rather rare phenomenon. In this study giant desmosomes were found in only 2 out of 10 cases of mesothelioma.